Don't clear the string stub at gc time in KeyedLoadIC.

Don't clear the string stub at gc time in KeyedLoadIC.

Clearing this stub doesn't actually make sense, as it neither leaks
memory, nor prevents finding a new optimum stable state. As
long as strings receivers are observed, this is the best stub.
The moment we see a non-string receiver we'll go polymorphic
or generic depending on the case.

R=yangguo@chromium.org

Committed: https://code.google.com/p/v8/source/detail?r=24360

[mvstanton, 2014-09-26 11:47:23]

mvstanton@chromium.org changed reviewers:
+ yangguo@chromium.org

[mvstanton, 2014-09-26 12:15:45]

Hi Yang,
Here is the change I was jawing about. :)
Thanks,
--Michael

[Yang, 2014-09-26 12:16:23]

On 2014/09/26 12:15:45, mvstanton wrote:
> Hi Yang,
> Here is the change I was jawing about. :)
> Thanks,
> --Michael

lgtm.

[mvstanton, 2014-10-01 11:09:14]

Committed patchset #1 (id:1) manually as 24360 (presubmit successful).